Airtel — refund not received for my dth account disconnection

I had placed a request to cancel my airtel dth connection on 9th oct 2017 due to bad services provided them. All the equipment's were recovered by airtel representative within 3-4 days of my request. It's now more than a month that i am still waiting for my refund but everytime i call the customer care team they tell me that there is no such request for disconnection placed for your connection and they place a new disconnection request everytime. I have also reached out to their nodal office email id and even they reply to me saying that we are working on it and will be resolved soon however i do not see any progress on my request. Instead they are placing some new requests on their own for my account like recharge request. Now i dont know whom to reach out to get my refund. I had recharged the annual pack for rs. 5500 which was not even used for more than 45-50 days. Please take my case to the appropriate person to help me get this resolved.